If you want to ensure best user experience for your app users you just must integrate this two API in your app. First of two is Get Satisfaction iPhone API. Satisfaction Remote Component enables iPhone developers to embed support for Get Satisfaction within their apps. This works somewhat like the “Feedback” widget on many websites (example on getsatisfaction.com homepage). Briefly, this API is integrates feedback forum for user. It has all features like one on websites and it is very confident. For one that doesn’t know what GS Remote Component is here you can find little more information about this great API.

http://code.google.com/p/satisfactionremotecomponent/ 

Flurry Analytics iPhone API is second one. This is really great API that every better developer would integrate. This API is analytics tool for iphone application which provides complete insight analysis of the every app utilization and not just for iPhone platform. Here is little info about it: “Flurry Analytics provides accurate, real time data to developers about how consumers use their mobile applications, as well as how applications are performing across different handsets. Application developers receive aggregated usage and performance data, as well as robust reporting and analysis tools. With this data, developers can identify issues and opportunities, create a more informed product roadmap, increase retention and grow their user base.” You can find more info on this link. 

http://www.flurry.com/product/index.html

From past experience I can confirm that our app users are very satisfied with services that these two tools give them, together with us.